Rotary ultrasonic bonder or processor capable of fixed gap operation

ABSTRACT

A method and apparatus ( 20 ) for ultrasonic bonding or other processing can include a rotatable ultrasonic horn member ( 28 ) having a first axial side ( 30 ) and a second axial side ( 32 ). The first axial side ( 30 ) of the horn member ( 28 ) can be operatively joined to a first rotatable axle member ( 34 ), and the first axle member ( 34 ) can be operatively joined to a first isolation member ( 42 ). The second axial side ( 32 ) of the horn member ( 28 ) can be operatively joined to a second rotatable axle member ( 36 ), and the second axle member ( 36 ) can be operatively joined to a second isolation member ( 44 ). The isolation members ( 42, 44 ) are capable of bending under a horn-life range of sonic frequencies to provide an operative component of motion along a radial direction ( 102 ) of each isolation member ( 42, 44 ), and an operative component of motion along an axial direction ( 100 ) of each isolation member.

FIELD OF THE INVENTION

[0001] This invention generally relates to a method and apparatus that can be employed for ultrasonic processing operations. In particular features, the method and apparatus can include a rotary ultrasonic horn, and the ultrasonic processing can include an ultrasonic bonding operation. More particularly, the invention relates to an ultrasonic processing method and apparatus which can provide for an operative isolation of the rotary horn while employing a connection system that has relatively high rigidity and stiffness.

BACKGROUND OF THE INVENTION

[0002] Conventional ultrasonic systems have included a rotary horn which cooperates with a rotary anvil. The conventional rotary ultrasonic horns have been supported and mounted by employing rubber or other elastomeric components to provide ultrasonic isolation. As a result, the ultrasonic horn has exhibited low static stiffness, low dynamic stiffness, and has exhibited excessively large amounts of run-out or other displacements during ordinary operation. Additionally, the conventional ultrasonic horn systems have employed complicated and unreliable torque transmission techniques.

[0003] To help address the various shortcomings, the conventional ultrasonic bonding systems have employed additional support wheels to help maintain the ultrasonic horn in a desired position relative to the cooperating rotary anvil. Typically, the support wheels have been configured to hold the rotary horn in a substantially continuous, direct contact with the rotary anvil during ordinary operation. The use of such support wheels, however, has excessively increased the audible noise from the system, and has caused excessive wear on the working surface of the ultrasonic horn. Additionally, the horn has exhibited uneven wear, or has required the use of an oscillation mechanism to more evenly distribute the wear. Torque transmission systems needed for driving the rotary horn have been excessively costly, have required excessive maintenance, and have been difficult to setup and adjust. The conventional ultrasonic horn systems have also created areas on the working surface of the horn that have been unsuitable for performing desired bonding operations, and have not provided sufficient levels of dynamic stability. Additionally, the conventional ultrasonic bonding systems have required excessively critical adjustments, and have exhibited excessive complexity and excessive costs. Where rubber or other elastic materials are employed to provide acoustic isolation mounts, the mounts can generate excessive reflected energy if the elastomeric material is over compressed. As a result, there has been a continued need for improved ultrasonic bonding systems.

BRIEF DESCRIPTION OF THE INVENTION

[0004] A processing method and apparatus can include a rotatable ultrasonic horn member operatively joined to a first isolation member, and second isolation member. In a particular feature, the first isolation member can exhibit high rigidity. In a further feature, the first isolation member can be capable of bending under a horn-life range of sonic frequencies to provide an operative component of motion along its radial direction and an operative component of motion along its axial direction. In another feature, the second isolation member can exhibit high rigidity. In still another feature, the second isolation member can be capable of bending under the horn-life range of sonic frequencies to provide an operative component of motion along its radial direction, and an operative component of motion along its axial direction.

[0005] In a particular aspect, each isolation member can have a radial isolation component and an axial isolation component. Each radial isolation component can be operatively joined to a corresponding axle member, and can be configured to extend at least radially from its corresponding axle member. The radial isolation component can be configured to operatively bend under the horn-life range of sonic frequencies. Each axial isolation component can be operatively joined to an operative portion of a corresponding radial isolation component, and can be configured to extend at least axially from its corresponding radial isolation component. The axial isolation component can be configured to operatively bend under the horn-life range of sonic frequencies.

[0006] The various aspects, features and configurations of the method and apparatus of the invention can provide a distinctive, rotary ultrasonic horn system which includes a corresponding wave-guide and at least one isolation member which has high rigidity and stiffness. The isolation member can operably isolate the radial motion that can arise at the longitudinal node of a wave-guide, and can provide sufficient bandwidth to compensate for nodal shifts that can occur during ordinary operation. The isolation member can also provide improved stiffness to reduce deflections under load. The increased stiffness can help maintain concentricity, and help to reduce run-out displacements. Additionally, the isolation member can more efficiently transmit torque and can provide improved effectiveness and efficiency. The isolation member can also be configured to reduce stress concentrations and to increase fatigue resistance, and can provide for a mounting system that can reduce relative motions between component parts. The method and apparatus of the invention can reduce the need for elastomeric isolation components, and can eliminate the need for conventional elastomeric O-rings and associated isolation-ring hardware. The method and apparatus can also reduce the need for torque transmission keys, and can avoid the use of auxiliary support wheels for maintaining the desired locations of the rotary horn and rotary anvil.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The invention will be more fully understood and further advantages will become apparent when reference is made to the following detailed description of the invention and to the drawings in which:

[0008]FIG. 1 shows a schematic, side view of a representative method and apparatus that may incorporate the present invention;

[0009]FIG. 2 shows a schematic, end view of a representative method and apparatus that may incorporate the present invention;

[0010]FIG. 3 shows a representative, perspective view of a representative horn member and isolation member that can be employed with the method and apparatus of the invention;

[0011]FIG. 4 shows a schematic view of a cross-section through a rotatably mounted configuration of the horn member and isolation member illustrated in FIG. 3;

[0012]FIG. 5 shows a representative, perspective view of another horn member and isolation member that can be employed with the method and apparatus of the invention;

[0013]FIG. 6 shows a schematic view of a cross-section through a rotatably mounted configuration of the horn member and isolation member illustrated in FIG. 5;

[0014]FIG. 6A shows a schematic view of a cross-section through an arrangement wherein the horn member and isolation member are rotatably mounted with a plurality of support bearings;

[0015]FIG. 7 shows a schematic side view of a representative horn member and isolation member mounted with associated components on a substantially non-resilient bearing;

[0016]FIG. 8 shows a schematic view of a cross-section through the mounted horn member and isolation member illustrated in FIG. 7;

[0017]FIG. 9 a representative perspective view a horn member and isolation member which can be mounted with a pair of rigid, substantially non-resilient, support bearings;

[0018]FIG. 10 shows a schematic view of a cross-section through a configuration of a horn member and isolation member wherein the isolation member has an axial isolation component which is separately provided from the radial isolation component, and the axial isolation component is integrally formed with a cooperating coupler;

[0019]FIG. 10A shows a schematic view of a cross-section through another configuration of a horn member and isolation member wherein the isolation member has an axial isolation component which is separately provided from the radial isolation component, and the axial isolation component is integrally formed with a cooperating coupler;

[0020]FIG. 10B shows a schematic view of a cross-section through a configuration of a horn member and isolation member wherein the isolation member has an axial isolation component which is integrally provided with the radial isolation component, and the isolation member is integrally formed with a cooperating coupler;

[0021]FIG. 10C shows a schematic view of a cross-section through a configuration of a horn member and isolation member wherein a cooperating coupler is press-fitted into the axial isolation component of the isolation member;

[0022]FIG. 11 shows a representative, schematic, perspective view of a method and apparatus that can incorporate a configuration having a horn member mounted with an inter-spanning, bridge configuration, and including a pair of isolation members which have high rigidity and stiffness and are located at opposed sides of the horn member;

[0023]FIG. 12 shows a representative, end view of a horn member that has been mounted in a bridge configuration with a pair of isolation members that have high rigidity and stiffness;

[0024]FIG. 13 shows a representative view of a cross-section through the horn member and dual isolation members that are illustrated in FIG. 12;

[0025]FIG. 13A shows a representative view of a cross-section through an arrangement wherein a plurality of ultrasonic exciters are operatively connected to the horn member;

[0026]FIG. 14 shows a representative, perspective view of a horn member and cooperating anvil member in a configuration that can be employed with a method and apparatus of the invention;

[0027]FIG. 15 shows a representative end view of the apparatus and method illustrated in FIG. 14.

DETAILED DESCRIPTION OF THE INVENTION

[0028] The method and apparatus that incorporates the present invention can be employed with any operative ultrasonic processing operation. Representative examples of such processing operations can include ultrasonic cutting, perforating, bonding, welding, embossing, crimping, heat activation or the like, as well as combinations thereof.

[0029] In the present disclosure, the terms “bonding” and “welding” may be used interchangeably, and refer to the substantially permanent joining of at least one layer of a material with another layer of a like or different material. The nature of the materials to be bonded is not known to be critical. However, the present invention is particularly useful in the bonding of two or more layers of materials, such as woven fabrics, nonwoven fabrics, and films.

[0030] The term “fabric” is used broadly in the present disclosure to mean a sheet or web of a woven or nonwoven fibrous material. The fabric or film layer may be continuous, as in a roll, or may be discontinuous.

[0031] The materials ultrasonically processed by the method and apparatus may include thermoplastic polymers or other thermoplastic materials. Alternatively, the processed materials may not include a thermoplastic material.

[0032] The representative configurations of the method and apparatus will, for example, be disclosed and described with reference to an ultrasonic bonding operation. It should be apparent that an adequate bonding or welding can be achieved by a variety of mechanisms. For example, the bond can result from the partial or complete melting in the bonding zone of all of the materials to be bonded. In this case, there is partial or complete fusion in the bonding area of such materials. Alternatively, the bond can result from the partial or complete melting of one of the materials to be bonded, with the partially or completely melted material flowing into or onto adjacent materials which in turn results in a mechanical interlocking of one material with another.

[0033] The present disclosure will be expressed in terms of its various components, elements, constructions, configurations and arrangements that may also be individually or collectively be referenced by the terms, “aspect(s)” of the invention, feature(s) of the invention, or other similar terms. It is contemplated that the various forms of the disclosed invention may incorporate one or more of its various features and aspects, and that such features and aspects may be employed in any desired, operative combination thereof.

[0034] It should also be noted that, when employed in the present disclosure, the terms “comprises”, “comprising” and other derivatives from the root term “comprise” are intended to be open-ended terms that specify the presence of any stated features, elements, integers, steps, or components, and are not intended to preclude the presence or addition of one or more other features, elements, integers, steps, components, or groups thereof.

[0035] The technology of the invention can be configured to produce various types of desired articles. Such articles may, for example, be gowns, covers, wraps, drapes, garments, packaging or the like. The articles may also be absorbent articles, and the absorbent articles may include infant diapers, children's training pants, feminine care articles, adult incontinence garments, and the like. The articles may be disposable, and intended for limited use. Typically, the disposable articles are not intended for washing and reuse.

[0036] With reference to FIGS. 1 and 2, the process and apparatus of the invention can have a lengthwise, machine-direction 24 which extends longitudinally, a lateral cross-direction 26 which extends transversely, and a z-direction. For the purposes of the present disclosure, the machine-direction 24 is the direction along which a particular component or material is transported length-wise along and through a particular, local position of the apparatus and method. The cross-direction 26 lies generally within the plane of the material being transported through the process, and is aligned perpendicular to the local machine-direction 24. The z-direction is aligned substantially perpendicular to both the machine-direction 24 and the cross-direction 26, and extends generally along a depth-wise, thickness dimension.

[0037] With reference to FIGS. 1, 2 and 5, the various components employed with the method and apparatus can have an axial direction 100, a radial direction 102, and a circumferential direction 104. The axial direction 100 extends along an appointed rotational axis of a selected component or member. The radial direction 102 extends radially from the rotational axis, and is substantially perpendicular to the rotational axis of the selected component or member. The circumferential direction 104 is directed along an orbital path around the rotational axis of the selected component or member, and is aligned substantially perpendicular to the radial direction 102 and substantially perpendicular to the axial direction 100.

[0038] As illustrated in FIGS. 1 and 2, a representative method and apparatus 20 for ultrasonically processing a target material 98 can include a rotary, ultrasonic horn member 28, and a cooperating, rotary ultrasonic anvil member 86. In a particular configuration, the method and apparatus can be arranged to provide a bonding operation. The rotatable anvil member 86 can be cooperatively positioned proximate the horn member 28, and an ultrasonic power source or exciter 82 can be operatively connected to the horn member. Typically, the horn member and anvil member can be configured to counter-rotate with respect to each other, and provide a nip region therebetween where the ultrasonic bonding operation can be conducted. A suitable horn drive 92 can be configured to rotate the horn member, and a suitable anvil drive 94 can be configured to rotate the anvil member. The horn drive and anvil drive may be provided by individual, separately provided driving mechanisms, or may be provided by the same driving mechanism. In a particular arrangement, the horn member may be rotated by the selected driving mechanism, and the anvil member may be driven by a contact pressure that is generated in the nip region between the horn member 28, target work material 98 and anvil member 86. Suitable driving systems can include take-offs from a powered line shaft, motors, engines, electric motors or the like, as well as combinations thereof.

[0039] The rotatable anvil member 86 has a rotational axis 114, and can be rotated by its corresponding rotational drive 94 to provide a minimum, anvil speed at its outer peripheral surface 90. In a particular aspect, the anvil peripheral speed can be at least a minimum of about 5 m/min. The anvil peripheral speed can alternatively be at least about 7 m/min, and optionally, can be at least about 9 mlmin to provide improved performance. In another aspect, the anvil peripheral speed can be up to a maximum of about 700 m/min, or more. The anvil peripheral speed can alternatively be up to about 600 m/min, and optionally, can be up to about 550 m/min to provide improved effectiveness. The anvil speed may be substantially constant, or may be non-constant or variable, as desired.

[0040] As representatively shown, the anvil member 86 can have a substantially circular, disk-shape, and an outer peripheral surface 90 of the anvil member may be substantially continuous. Alternatively, the anvil member may have a non-circular shape. Additionally, the outer peripheral surface of the anvil member may be discontinuous. Optionally, the anvil member may have a shape composed of one or more spoke or lobe members, and the spoke or lobe members may have the same size and/or shape, or may have different sizes and/or shapes.

[0041] The horn member 28 has a rotational axis 112, and can be rotated by its corresponding rotational drive 92 to provide a horn speed at its outer peripheral surface 88 which substantially equals the anvil peripheral speed. Optionally, the peripheral speed of the horn member 28 can be mismatched and unequal to the peripheral speed of the anvil member 86.

[0042] As representatively shown, the horn member 28 can have a substantially circular, generally disk-shape, and an outer peripheral surface 88 of the horn member may be substantially continuous. Optionally, the horn member may have a non-circular shape. Additionally, the outer peripheral surface of the horn member may have a discontinuous configuration.

[0043] An ultrasonic exciter 82 can be operatively connected to direct a sufficient amount of ultrasonic power into the horn member 28 through suitable, ultrasonic wave-guides, booster members, and connection/transmission components. Suitable ultrasonic exciters, ultrasonic connectors, ultrasonic boosters and ultrasonic wave-guides are well known in the art and are available from commercial vendors.

[0044] With reference to FIGS. 3 through 9, a desired method and apparatus 20 for bonding or other processing can include a rotatable ultrasonic horn member 28 and a rotatable axle member 34. The horn member can have a first axial side 30 and a second axial side 32. The axle member can be operatively joined to the horn member 28, and an isolation member 42 can be operatively connected to the horn member 28. In a particular aspect, the isolation member 42 is capable of dynamically flexing and bending under a horn-life range of sonic frequencies to provide an operative component of motion along a radial direction 102 of the isolation member, and can provide an operative component of motion along an axial direction 100 of the isolation member.

[0045] With reference to FIGS. 11 through 15, the processing method and apparatus 20 can include a rotatable ultrasonic horn member 28. The first axial side 30 of the horn member 28 can be operatively joined to the first rotatable axle member 34, and the first axle member 34 can be operatively joined to the first isolation member 42. In a desired feature, the first isolation member can exhibit high rigidity. In another feature, the first isolation member 42 is capable of bending under a horn-life range of sonic frequencies to provide an operative component of motion along its radial direction 102 and an operative component of motion along its axial direction 100. The second axial side 32 of the horn member 28 can be operatively joined to a second rotatable axle member 36, and the second axle member 36 can be operatively joined to a second isolation member 44. In a desired feature, the second isolation member can exhibit high rigidity. In another feature, the second isolation member 44 is capable of bending under the horn-life range of sonic frequencies to provide an operative component of motion along a radial direction of the second isolation member 44, and an operative component of motion along an axial direction of the second isolation member 44.

[0046] In other aspects, the axle member 34 can provide a node plane 38, and the isolation member 42 can be located operatively proximate the node plane of the axle member. As illustrated in the representatively shown configuration, the axle member 34 can be configured to provide by an operative wave-guide which can direct ultrasonic energy from a suitable ultrasonic power source to the horn member.

[0047] In a like manner, the second axle member 36 can provide a second node plane 40, and the second isolation member 44 may be located operatively proximate the second node plane 40 of the second axle member 36. In particular configurations, the second axle member 36 can be configured to provide an operative wave-guide which can direct ultrasonic energy from a suitable ultrasonic power source to the horn member (e.g. FIG. 13A).

[0048] In particular configurations the axle member 34 may provide a node plane and/or an anti-node plane. The isolation member 42 may be positioned substantially at or closely adjacent its corresponding node plane; may be positioned substantially at or closely adjacent its corresponding anti-node plane; or may be positioned at a location that is spaced away from its corresponding node plane or anti-node plane; as desired.

[0049] In a like manner, the second axle member 36 may provide a node plane and/or an anti-node plane. The second isolation member 44 may be positioned substantially at or closely adjacent its corresponding, second node plane; may be positioned substantially at or closely adjacent its corresponding anti-node plane; or may be positioned at a location that is spaced away from its corresponding node plane or anti-node plane; as desired.

[0050] In further aspects, the isolation member 42 can have high rigidity and stiffness, and can be substantially non-elastomeric. The dynamic bending of the isolation member can be substantially non-elastomeric, and can be provided by a mechanism that is substantially free of a component constructed with an elastomer, such as natural or synthetic rubber. In still other aspects, the isolation member can provide a generally cantilevered flexing and bending. Additionally, the isolation member can provide for an operative component of bending or flexure displacement which is directed transverse the radial direction of the isolation member, and can provide for an operative component of bending or flexure displacement which is directed transverse to the axial direction of the isolation member.

[0051] In a like manner, the second isolation member 44 can have high rigidity and stiffness, and can be substantially non-elastomeric. The dynamic bending of the second isolation member can be provided by a mechanism that is substantially free of an elastomeric component. In still other aspects, the second isolation member can provide a generally cantilevered flexing and bending. Additionally, the second isolation member can provide for an operative component of bending or flexure displacement which is directed transverse the radial direction of the second isolation member, and can provide for an operative component of bending or flexure displacement which is directed transverse to the axial direction of the second isolation member.

[0052] In still another aspect, the isolation member 42 can have a radial isolation component 46 and an axial isolation component 50. The radial isolation component 46 can be operatively joined to the axle member 34, and can be configured to extend at least, substantially radially from the axle member 34. In a particular aspect, the radial isolation component can extend from the axle member with a generally cantilevered configuration. The radial isolation component 46 can be configured to operatively flex and bend under the horn-life range of sonic frequencies. Additionally, the radial isolation component can dynamically bend to provide transverse displacements that are directed along a thickness dimension of the radial isolation component. Accordingly, a dynamic bending of the radial isolation component can swing generally along the axial direction of the isolation member.

[0053] The axial isolation component 50 can be operatively joined to an operative portion of the radial isolation component 46, and can be configured to extend at least axially from the radial isolation component 46. In a particular aspect, the axial isolation component can extend from the radial isolation component with a generally cantilevered configuration. The axial isolation component 50 can be configured to operatively flex and bend under the horn-life range of sonic frequencies. Additionally, the axial isolation component can dynamically bend to provide transverse displacements that are directed along a thickness dimension of the axial isolation component. Accordingly, a dynamic bending of the axial isolation component can swing generally along the radial direction of the isolation member.

[0054] In a like manner, the second isolation member 44 can have a corresponding radial isolation component 48, and a corresponding axial isolation component 52. The second, radial isolation component 48 can be operatively joined to its corresponding, second axle member 36, and can be configured to extend at least, substantially radially from the axle member 36. In a particular aspect, the second radial isolation component can extend from its corresponding axle member with a generally cantilevered configuration. The second radial isolation components 48 can be configured to operatively flex and bend under the horn-life range of sonic frequencies. Additionally, the second radial isolation component 48 can dynamically bend to provide transverse displacements that are directed along a thickness dimension of the radial isolation component 48. Accordingly, a dynamic bending of the second, radial isolation component can swing generally along the axial direction of the second isolation member.

[0055] The second, axial isolation component 52 can be operatively joined to an operative portion of its corresponding, second radial isolation component 48, and can be configured to extend at least axially from the second radial isolation component. In a particular aspect, the second axial isolation component 52 can extend from its corresponding, second radial isolation component 48 with a generally cantilevered configuration. The second, axial isolation component 52 can be configured to operatively flex and bend under the horn-life range of sonic frequencies. Additionally, the second axial isolation component can dynamically bend to provide transverse displacements that are directed along a thickness dimension of the second axial isolation component. Accordingly, a dynamic bending of the second axial isolation component can swing generally along the radial direction of the second isolation member.

[0056] The various aspects, features and configurations of the method and apparatus, taken alone or in combination, can provide a distinctive, rotary ultrasonic horn system which includes a corresponding wave-guide, such as provided by the axle member 34, and at least one isolation member 42 that has high rigidity and stiffness. The isolation member can operably isolate the radial motion that can arise at the longitudinal node of the wave-guide, and can provide sufficient bandwidth to compensate for nodal shifts that can occur during ordinary operation. In particular, the isolation member can compensate for changes in the real-time location of the actual nodal plane that arises during the actual transfer of ultrasonic energy through the wave-guide. The isolation member can also provide improved stiffness to reduce deflections under load. The increased stiffness can help maintain concentricity, and help to reduce run-out displacements at the working surface of the horn member. Additionally, the isolation member can more efficiently transmit torque to the horn member, and can provide improved effectiveness and operating efficiency. The isolation member can also be configured to reduce stress concentrations and to increase fatigue resistance. Additionally, the isolation member can provide for a mounting system that can reduce relative motions between component parts. The method and apparatus can eliminate the need for elastomeric isolation components, such as conventional elastomeric O-rings and associated isolation ring hardware. The method and apparatus can also reduce the need for torque transmission keys, and can avoid the use of auxiliary support wheels for maintaining the desired locations of the rotary horn and rotary anvil.

[0057] Horn members that can be employed in the method and apparatus are well known in the art. For example, suitable rotary ultrasonic horn members are disclosed in U.S. Pat. No. 5,096,532 entitled ULTRASONIC ROTARY HORN by Joseph G. Neuwirth et al. which issued Mar. 17, 1992; U.S. Pat. No. 5,110,403 entitled HIGH EFFICIENCY ULTRASONIC ROTARY HORN by Thomas D. Ehlert et al. which issued May 5, 1992; and in U.S. Pat. No. 5,087,320 entitled ULTRASONIC ROTARY HORN HAVING IMPROVED END CONFIGURATION by Joseph G. Neuwirth which issued Feb. 11, 1992. The entirety of each of these documents is incorporated herein by reference, in a manner that is consistent herewith.

[0058] The incorporation of one or more wave-guides, such as provided by the axle member 34, is also well known in the art. The construction and arrangement of a suitable wave-guide is conventional, and can be conducted with commonly understood engineering techniques that are employed for ultrasonic processing systems, such as ultrasonic bonding systems.

[0059] For the present disclosure, the node plane of the selected wave-guide is a longitudinal node located along the axial direction of the method and apparatus. At the node plane, approximately zero longitudinal (e.g. axial) displacements are present during ordinary operation with the selected ultrasonic excitations. Radial displacements, however, can continue to occur at the longitudinal node.

[0060] Rotatable anvil members that can be employed in the method and apparatus are well known in the art, and are available from commercial vendors. Examples of such vendors include Sonobond, a business having offices located in West Chester, Pa.; and Branson Ultrasonics, a business having offices located in Danbury, Conn.

[0061] Conventional ultrasonic exciters and power sources can be employed in the method and apparatus of the invention, and are available from commercial vendors. Examples of suitable ultrasonic power systems include a Model 20A3000 system available from Dukane Ultrasonics, a business having offices located in St. Charles, Ill.; and a Model 2000CS system available from Herrmann Ultrasonics, a business having offices located in Schaumburg, Ill. In a particular aspect, the method and apparatus can include an ultrasonic exciter 82 which is operatively connected to the horn member 28, and is capable of providing an operative amount of ultrasonic energy at a frequency within the range of about 15-60 KHz (Kilo-Hertz). It should be appreciated that other operative ultrasonic frequencies may also be employed.

[0062] With reference to FIGS. 3 through 6A, at least one region of the isolation member 42 can bend under the selected horn-life range of sonic frequencies to provide an operative component of beam-type, flexing or bending displacement which is aligned generally transverse to the radial direction of the isolation member. In a particular aspect, the isolation member can provide for one or more regions that can exhibit one or more dynamic bending and flexing displacements or movements that are directed generally along the axial direction of the isolation member. For example, the radial isolation component 46 of the isolation member can be configured to provide for one or more dynamic bending and flexing displacements that can swing back-and-forth in a path that extends generally along the axial direction of the isolation member. In a desired aspect, the isolation member can move in the manner of an oscillating diaphragm. In a more particular aspect the radial isolation component 46 can move in the manner of an oscillating diaphragm.

[0063] The isolation member can also provide for one or more regions that can exhibit one or more beam-type bending and flexing displacements or movements that are directed generally transverse to the axial direction of the isolation member. In a particular aspect, the isolation member can provide for one or more regions that can exhibit one or more dynamic bending and flexing displacements or movements that are directed generally along the radial direction of the isolation member. For example, the axial isolation component 50 can be configured to provide for one or more dynamic bending and flexing displacements that can vibrationally swing back-and-forth in a path that extends generally along the radial direction of the isolation member. It should be readily appreciated that, in additional to the described bending and flexing displacements exhibited by the isolation member 42, the isolation member may experience other dynamic motions that are typically induced during ordinary ultrasonic bonding operations.

[0064] In a like manner, the second isolation member 44 can bend under the horn-life range of sonic frequencies to provide an operative component of flexing and bending or other motion along the radial direction of the second isolation member, and can provide an operative component of flexing and bending or other motion along the axial direction of the second isolation member. The flexing and bending along the radial and/or axial direction can be provided without excessive fatigue of the second isolation member 44. Where the second isolation member 44 has particular radial and/or axial isolation components 48 and 52, each of the radial and/or axial isolation components can be configured to bend without excessive fatigue. It should be readily appreciated that the second isolation member 44 can cooperatively have a configuration and operation that is similar to those provided by the first isolation member 42. Accordingly, the various parameters and descriptions that are described with respect to the first isolation member 42 would also pertain to the second isolation member 44, as well as to any other additionally employed isolation members.

[0065] It has been discovered that the traversing, dynamic bending and flexing displacements that can be induced generally along the axial direction and/or radial direction can help compensate for any mismatch between the location of the isolation member and the location of the associated node plane. In a more particular aspect, the traversing dynamic bending and flexing displacements can help compensate for any mismatch between (a) the physical location at which the isolation member 42, 44 connects to its corresponding axle member 34, 36, respectively, and (b) the actual location of the corresponding dynamic node plane 38, 40 along the axial length of the corresponding axle member 34, 36, respectively. Such mismatches can occur during the operation of the method and apparatus due to shifts caused by changes in temperature, changes in ultrasonic-frequency, changes in the target work material or the like, as well as combinations thereof.

[0066] The dynamic flexing and bending displacements that are transverse to the radial and/or axial direction of the isolation member can desirably be provided without generating excessive fatigue of the corresponding isolation member. Where the particular isolation member has a discretely identifiable, radial isolation components 46, 48 and/or a discretely identifiable, axial isolation components 50, 52, each of such radial and/or axial isolation components can each be configured to bend without excessive fatigue by employing conventional parameters and design techniques that are well known in the art. For example, the length, thickness, elastic modulus, and other parameters can be selected and configured to provide the operative bending and fatigue resistance of the radial isolation component. Similarly, the length, thickness, elastic modulus, and other parameters can be selected and configured to provide the operative bending and fatigue resistance of the axial isolation component.

[0067] In a particular aspect, the isolation member can operate under its intended, ordinary operating conditions for a minimum of about 4000 hours without excessive fatigue failure. The isolation member can desirably provide a minimum ultrasonic operating life of about 5000 hours substantially without fatigue failure, as determined under its intended, ordinary operating conditions, and can more desirably provide a minimum ultrasonic operating life of about 6000 hours substantially without fatigue failure.

[0068] In a particular aspect, the isolation member can be configured such that during ordinary operation, the isolation member will be subjected to a stress level that is not more than about 10% of the yield strength of the isolation member. Alternatively, the isolation member can be configured such that during ordinary operation, the isolation member will be subjected to a stress level that is not more than about 1% of the yield strength of the isolation member.

[0069] The isolation member can be configured to operatively bend and swing back-and-forth under a horn-life range of sonic frequencies to provide an operative component of motion along a radial direction and an operative component of motion along an axial direction. The horn-life range of frequencies can be a range that is about ±3% of the nominal ultrasonic frequency. The nominal frequency is the target ultrasonic frequency at which the method and apparatus is intended to operate to perform the selected processing operation.

[0070] In the various configurations of the method and apparatus of the invention, the radial isolation component can extend discontinuously or substantially continuously along a circumferential direction of the isolation member. With reference to FIGS. 3 through 6A, the representatively shown radial isolation component 46 can be substantially disk-shaped, or can be substantially annular-shaped, as desired.

[0071] With reference to FIGS. 3 through 8, the axial isolation component 50 can be configured to provide a substantially axial extension from the radial isolation component 46. In the example of the representatively shown arrangement, the axial isolation component 50 can be configured to provide an extension which is directed along the axial direction from a radially outboard section of the radial isolation component 46. The axial isolation component can be configured to provide a discontinuous or a substantially continuous axial extension from the radial isolation component. Additionally, the axial isolation component can be configured to extend discontinuously, or substantially continuously along a circumferential direction 104 of the isolation member. In the example of the representatively shown configuration, the axial isolation component 50 can be substantially cylinder-shaped.

[0072] In the various configurations of the invention, the horn member, the associated axle member or members and the cooperating isolation member or members can be components that are separately provided and operatively attached together. Alternatively, the horn member, the associated axle member(s) and the cooperating isolation member(s) may be integrally formed from a single piece of material that is suitable for constructing ultrasonic bonding devices. For example, the horn member, axle members and isolation members can be machined from the same piece of bar stock.

[0073] With regard to the isolation member 42, the axial isolation component 50 and the radial isolation component 46 can be separately provided pieces that are operatively attached together, or may be integrally formed from the same piece of material that is suitable for constructing ultrasonic bonding devices. For example, the axial isolation component and the radial isolation component can be formed from the same piece of bar stock material.

[0074] In an alternative configuration, the axial isolation component 50 can be separate from the radial isolation component 46. In another feature, the axial isolation component may be integrally formed with a cooperating coupler member 58. An appointed section of the axial isolation component can then be attached and secured to the separately provided, cooperating radial isolation component 46. As representatively shown in FIG. 10, the radial isolation component may be press-fitted into the axial isolation component. As illustrated in FIG. 10A, the radial isolation component may be bolted or otherwise secured to the axial isolation component.

[0075] In an optional arrangement, the isolation member 42 can have an axial isolation component 50 which is integrally provided with the radial isolation component 46, and the isolation member can be integrally formed with its cooperating coupler, as representatively shown in FIG. 10B. The radial isolation component can be operatively attached to the axle member 34 with any suitable securement system.

[0076] Another arrangement of the isolation member 42 can have the cooperating coupler 58 press-fitted into the axial isolation component 50 of the isolation member 42, as illustrated in FIG. 10C. It should be readily appreciated that the axial isolation component 50, radial isolation component 46 and axle member 34 can additionally be interconnected together in any operative configuration.

[0077] The method and apparatus can include at least one, and optionally a plurality, of rotational couplers, such as provided by one or more couplers 58 and 60. In the various arrangements of the invention, each coupler can be configured to be operatively similar to some or all of the other couplers. Accordingly, the arrangements, structures features, operational features or other configurations that are described with respect to a particular coupler may also be incorporated by the other couplers.

[0078] As representatively shown in FIGS. 4 through 10C, the isolation member 42 can be joined to a rotatable coupler 58 which, in turn, can be supported by at least one rotational bearing 66 and associated mounting structure. Accordingly, the coupler 58 can interconnect between the isolation member 42 and the rotational bearing 66. In a desired configuration, the rotational bearing 66 and a corresponding mount 70 can fixedly hold and support the rotatable coupler 58. The bearing mount can be positioned generally adjacent the node plane of the axle member. Alternatively, the bearing mount can be spaced from the node plane of the axle member by a significant distance. As representatively shown, the bearing support mount 70 can be positioned generally adjacent the node plane 38 provided by the axle member 34.

[0079] With reference to FIGS. 6A and 9, the horn member 28 can be held in a cantilevered position with a plurality of bearing members 66 and 66 a and associated support mounts 70 and 70 a. The coupler 58 can be extended along its axial dimension, and a pair of bearing members can be arranged with one bearing member located proximate each axial end of the coupler. The bearing members can be attached to their corresponding support mounts in a manner that can hold the coupler in a substantially fixed position that exhibits high rigidity and stiffness. Appropriate booster members and wave-guides can be configured to extend through the coupler and operably connect to the axle member 34 and horn member 28.

[0080] In a particular aspect, the method and apparatus of the invention can be configured to provide a rotatable horn member 28 which exhibits a very low static deflection. In a desired configuration, the static deflection can be about 0.025 mm (about 0.0005 inch) or less, when subjected to a static force of 445 N (100 lb) which is directed against the outer peripheral surface 88 of the horn member 28 at a location that is centered along the axial dimension of the surface 88, and along the radial direction of the rotatable horn. In other configurations, the static deflection can be up to a maximum of about 0.76 mm (about 0.03 inch). The horn deflection can alternatively be not more than about 0.5 mm (about 0.02 inch), and can optionally be not more than about 0.3 mm (about 0.012 inch) to provide improved effectiveness. In a particular arrangement, the static deflection of the horn member can be not more than about 0.076 mm (about 0.003 inch).

[0081] In another aspect, a second bearing support mount 72 can be employed to support the horn member in a spanning, bridge configuration (e.g. FIGS. 12 and 13). The second mount 72 may be positioned generally adjacent the second node plane 40 provided by the second axle member 36, and can fixedly hold and support the second rotatable coupler 60. Alternatively, the bearing mount can be spaced from the node plane of the axle member by a significant distance. As representatively shown, the second support mount 72 can be positioned generally adjacent the node plane 40 provided by the axle member 36.

[0082] The method and apparatus of the invention can additionally be configured to provide a rotatable horn member 28 which exhibits a static deflection of about 0.004 mm (about 0.00015 inch), or less, when subjected to a static force of 445 N (100 lb) which is directed onto the outer peripheral surface 88 of the horn member 28 at a location that is centered along the axial dimension of the surface 88, and along the radial direction of the rotatable horn. In particular aspects, the horn deflection can alternatively be about 0.002 mm or less, and can optionally be 0.001 mm or less. In other aspects, the horn deflection can be not more than a maximum of about 0.075 mm. The horn deflection can alternatively be not more than about 0.05 mm, and optionally, can be not more than about 0.01 mm to provide further improved performance.

[0083] The method and apparatus can further be configured to provide a rotatable horn member 28 which exhibits distinctively low level of dynamic run-out. In a desired feature, the horn run-out can be about 0.0025 mm (about 0.00001 inch) or less, at a rotational speed of 5 revolutions/minute. In a further feature, the horn member can exhibit a maximum run-out of not more than about 0.018 mm (about 0.0007 inch). The horn run-out can alternatively be not more than about 0.013 mm (about 0.0005 inch), and can optionally be not more than about 0.01 mm (about 0.0004 inch) to provide improved performance.

[0084] The configurations of the method and apparatus that have the rotary horn member 28 with high-rigidity isolation members 42, 44 disposed at axially opposed sides of the horn member are particularly capable of providing the desired low levels of horn deflection and run-out. Additionally, the high-rigidity holding of the isolation members 42, 44 in a substantially fixed position with the rotational bearings 66, 68 and their correspondingly associated support mounts 70, 72 can further help to provide and maintain the small amounts of horn deflection and run-out.

[0085] With reference to the aspects of the invention illustrated in FIGS. 3 through 6A, the isolation member 42 can have a generally annular-shaped, radial isolation component 46 which has high rigidity and stiffness, and is connected and attached to the wave-guide provided by axle member 34. The attachment is positioned at approximately the expected node plane of the wave-guide, axle member. A generally cylindrical-shaped axial isolation component 50 can have high rigidity and stiffness, and can be connected and attached to a distal outer edge region of the radial isolation component 46. The axial isolation component can extend from the radial isolation component in an inboard direction toward the horn member 28, or in an outboard direction away from the horn member. Alternatively, the axial isolation component can extend in both the inboard and outboard directions.

[0086] As illustrated in the arrangements shown in FIGS. 3 and 4, the axial isolation component 50 may extend in both the inboard and outboard directions by substantially equal distances. Optionally, the axial isolation component may extend in both the inboard and outboard directions by different, unequal distances. The axial isolation component 50 can include one or more radially projecting, substantially annular spacers 51 which hold the axial isolation component at a spaced distance from its corresponding coupler 58. As representatively shown, each of a pair of spacers 51 can be located each opposed, axial end of the axial isolation component. The spaced distance is configured to allow an operative amount of dynamic, bending flexure of the axial isolation component.

[0087] With reference to the aspects of the invention illustrated in FIGS. 5, 6 and 6A, the isolation member 42 can include a generally annular-shaped, radial isolation component 46 which has high rigidity and stiffness, and is connected and attached to the wave-guide provided by axle member 34. The attachment is positioned at approximately the expected node plane of the wave-guide, axle member. A generally cylindrical-shaped axial isolation component 50 is configured to have high rigidity and stiffness, and is connected and attached to an outer edge region of the radial isolation component 46. The axial isolation component can extend from the radial isolation component in an outboard direction away from the horn member.

[0088] In the various arrangements of the method and apparatus, the configuration of the attachment or other operative connection between the axle member and its corresponding, connected isolation member can be substantially free of rubber or other elastomeric components. Accordingly, the attachment mechanism can provide an operative connection that has high rigidity and stiffness, and is substantially non-resilient.

[0089] The isolation member 42 can include a diaphragm-like element and a mounting flange 54. The diaphragm-like element can include a substantially continuous radial component 46 which has high rigidity and stiffness, and extends substantially radially from the axle member 34 or other wave-guide. Additionally, the radial component 46 can be positioned at approximately the nodal plane 38 of the axle member or other wave guide. The radial component can project radially outward with a length that can allow this radial component to operatively bend under normal horn-life frequency ranges without sacrificing fatigue life. Moving outward from the radial component, the structural shape of the isolation member 42 can transition to provide an axial component 50 which extends along the axial direction of the isolation member. As representatively shown, the axial component can have a generally cylinder-shape that projects substantially parallel to the rotational axis of the wave-guide or axle member 34.

[0090] The lengths of the radial and axial components of the isolation member 42 are long enough to allow these components to dynamically flex and bend through the normal range of radially and axially-directed motions that can arise at or near the node of a wave-guide during its intended operation. In particular, the axial length of the cylinder-shape can dynamically flex and bend through the normal range of radially directed motions that can arise at or near the node of a wave-guide. Such radially-directed motion can ordinarily arise from resonant oscillations caused by the ultrasonic energy directed into the horn member 28. The radial length of the diaphragm-shape can dynamically flex and bend through the normal range of axially-directed motions that can arise at or near the node of a wave-guide. Such axially-directed motion can also arise from resonant oscillations caused by the ultrasonic energy directed into the horn member 28. The combination of the dynamic bending movements of the radial and axial components of the isolation member can act to dampen the radial and axial motions induced in the horn 28 and wave-guide (e.g. axle member 34) during the normal, oscillatory expansions and contractions that are excited by the ultrasonic power source. The dampening can occur through the normal range of ultrasonic frequencies to which the horn 28 is subjected during ordinary operation.

[0091] At a selected region, such as at an extreme outer diameter of the isolation member 42, an operative fastening/affixing mechanism or method can be employed to attach and secure the isolation member to other components of the ultrasonic bonding system, such as the coupler 58. As representatively shown, for example, the fastening mechanism can be located at an extreme outer diameter of the axial isolation component 50. In one arrangement, the isolation member 42 (e.g. the axial isolation component 50 of the isolation member) can include an extending flange portion 54. As representatively shown, the joining flange 54 can include a generally radially extending section and may include a generally axially extending section. In a desired aspect, the joining flange can be operatively positioned and secured in the coupler opening 62. In another aspect, the coupler flange portion 54 can be operatively affixed to the coupler opening 62 by including an interference, friction-fit. The flange can, for example, be press-fit into a bore opening, such as that provided by the coupler opening 62, and may additionally or alternatively be held in place by fasteners.

[0092] Alternatively, an interference, friction-fit can be generated by heat-expanding the part having the appointed opening (e.g. coupler opening 62), and inserting into the expanded opening the component or component part that is intended to be captured or held (e.g. isolation member 42). When the heat dissipates, the opening can contract and help secure the inserted component.

[0093] In another fastening arrangement, the flange can be appropriately extended, as needed, and a clamping arrangement can be employed to hold the isolation member in place. Yet another fastening arrangement could incorporate a single extension having a surface suitable for clamping.

[0094] In a further aspect, the connecting flange can be substantially contiguously and integrally formed with its corresponding isolation member 42. Optionally, the flange may be a separately provided component that is subsequently affixed to the isolation member. Additionally, the isolation member can substantially continuously and integrally formed with its corresponding wave-guide or axle member 34. Accordingly, the horn can more accurately be held in a selected position, can better maintain a desired position when subjected to a much greater load. Additionally, a desired rotational driving torque can be more efficiently transmitted to the horn 28.

[0095] In a desired feature, the coupler can provide a holding and securing force that is distributed substantially evenly around the circumference of the axial isolation component. For example, the coupler can provide a substantially evenly distributed, compressive securing force that is directed substantially radially-inward against the axial isolation component. Optionally, the axial isolation component may provide a substantially evenly distributed, compressive securing force that is directed substantially radially-inward against the coupler.

[0096] The coupler 58 can provide a coupler opening 62 into which the first isolation member 42 is operatively positioned and secured. In a particular aspect, the axial isolation component 50 of the isolation member 42 can be operatively positioned and secured in the coupler opening 62 (e.g. FIGS. 4 and 6). For example, the coupler 58 can provide a substantially cylinder-shaped, coupler opening 62 into which the axial isolation component 50 of the isolation member 42 can be operatively positioned and secured. The isolation member may, for example, be press-fitted into the coupler opening.

[0097] Optionally, the axial isolation component can be configured to provide an isolation-member opening, and an operative end-portion of the coupler can be operatively positioned and secured in the isolation-member opening. For example, the coupler may be press-fitted into the opening of the isolation member.

[0098] As representatively shown, the coupler 58 can be configured to provide a tube structure through which other components may be operably located and directed. With reference to FIGS. 4 and 8, for example, the axle member 34 can be co-linearly or coaxially arranged with respect to the coupler, and the axle member can extend through the coupler. Additionally, an ultrasonic booster member 74 can be co-linearly or coaxially arranged with respect to the coupler, and the booster member can extend through the coupler. The booster member can further be operatively connected to the axle member 34, and an ultrasonic exciter 82 can be operably connected to the booster member 74 by employing any conventional technique or device. For example, electrical power can be directed with suitable electrical conductors to a conventional slip ring 78 assembly, and the slip ring assembly can be employed to operatively direct the electrical power to the ultrasonic exciter 82. The exciter can use the electrical power to generate the desired ultrasonic energy, and direct the ultrasonic energy to the horn member 28. As representatively shown, the ultrasonic energy can be directed into the booster member 74, through the axle member 34 and into the horn member.

[0099] The method and apparatus can be suitably mounted on a support frame 22. The coupler member 58 can be substantially non-resiliently supported with a mounting system that is substantially non-elastomeric and has relatively high rigidity and stiffness. The mounting system can be substantially free of components constructed with an elastomer, such as natural or synthetic rubber. In a particular feature, the rotational bearing 66 can be substantially non-resiliently mounted, and the mounting system can be substantially free of elastomeric mounting elements, such as provided by elastomeric O-rings. The support frame is desirable constructed with a suitable vibration-dampening material. Various conventional dampening materials are well known in the art. For example, the frame may be constructed from iron, and the iron can have a dampening capacity of about 100-500.

[0100] A desired bonding pattern 96, or other selected processing mechanism, can be provided on the outer peripheral surface 90 of the rotary anvil member 86, or may be provided on the outer peripheral surface 88 of the rotary horn member 28, as desired. In the representatively shown configuration, the desired bonding pattern is provided on the outer surface circumferential 90 of the anvil member 86. The bonding pattern can be composed of a plurality of bonding elements 132 which are configured to project substantially radially away from the outer surface 90 of the anvil member 86, in a manner that is well known in the art. The bonding elements can be discontinuously or substantially continuously distributed in a regular or irregular array across the outer peripheral surface 90 of the anvil member 86, or the outer surface 88 of the horn member 28, as desired.

[0101] The method and apparatus can be substantially free of rotational supports that directly contact the rotary horn member 28. In particular, the method and apparatus can be substantially free of rotational supports that directly contact the outer peripheral surface 88 of the horn member 28.

[0102] In a further aspect, the method and apparatus can be substantially free of supports that directly contact the rotary anvil member 86 to maintain a selected position of the rotary anvil member relative to the rotary horn member. More particularly, the method and apparatus can be substantially free of rotational supports that directly contact the outer peripheral surface 90 of the anvil member 86.

[0103] With reference to FIGS. 11 through 13, the method and apparatus can incorporate a rotary ultrasonic horn that is mounted in an inter-spanning, bridge configuration, and is sonically isolated by employing a configuration that exhibits high rigidity and stiffness. In a desired configuration, the horn member 28 can be held by rotational bearings and associated support mounts that are substantially symmetrically disposed at axially opposed sides of the horn member. Accordingly, the horn member 28, the axle members 34 and 36 and the isolation members 42 and 44 can be configured to span between the couplers 58 and 60, and between the support mounts 70 and 72. A desired feature can have the axle members 34 and 36 and the corresponding isolation members 42 and 44 arranged in a substantially symmetrical configuration on each side of the horn member 28. Alternatively, the axle members 34 and 36 and the corresponding isolation members 42 and 44 arranged in a nonsymmetrical configuration on each side of the horn member.

[0104] The bridge-mounting of the horn can significantly reduce the problems of excessively low static stiffness and excessively high horn deflections that can excessively move the outer surface of the horn to positions that are out-of-plane with the desired bonding operation. Such undesired deflections of the horn member can move an outer surface 88 of the horn to a position that is excessively non-parallel with the outer surface 90 of the cooperating anvil member 86, as observed in the nip region between the horn and anvil members. The bridge-mounting of the rotary horn 28, the high-rigidity isolation members, the incorporation of precision bearings, and other features of the invention can help provide improved accuracy and stability.

[0105] In a further feature, the frame and other support assembly components can incorporate a high-damping material, such as provided by extruded-iron, and can be configured to provide a high degree of static and dynamic stiffness. The support assembly components can also be formed and configured to substantially avoid resonances when the horn is powered at ordinary excitation frequencies.

[0106] With reference to FIGS. 14 and 15, the method and apparatus can include a highly stiff and rigid frame 22 with associated support components for the horn and anvil members. In a particular feature, the frame can provide a substantially symmetrical configuration of mounting and support for the horn member 28, and can provide a substantially symmetrical configuration of mounting and support for the anvil member 86. In a further feature, the frame can help provide high levels of static and dynamic stiffness, and can help provide high levels of dynamic stability

[0107] As representatively shown, the rotatable ultrasonic horn member 28 has a first axial side 30 and a second axial side 32, and the first axial side 30 of the horn member 28 can be operatively joined to a first rotatable axle member 34 which is capable of providing a first node plane 38. The first axle member 34 can be operatively joined to a first isolation member 42 which has been located operatively proximate the first node plane 38 of the first axle member 34. In a particular aspect, the first isolation member 42 is capable of bending under a horn-life range of sonic frequencies to provide an operative component of motion along its radial direction 102 and an operative component of motion along its axial direction 100. The second axial side 32 of the horn member 28 can be operatively joined to a second rotatable axle member 36 which is capable of providing a second node plane 40. The second axle member 36 can be operatively joined to a second isolation member 44 which has been located operatively proximate the second node plane 40 of the second axle member 36. In a particular aspect, the second isolation member 44 is capable of bending under the horn-life range of sonic frequencies to provide an operative component of motion along a radial direction of the second isolation member 44, and an operative component of motion along an axial direction of the second isolation member 44.

[0108] In another aspect, the first isolation member 42 can have a first, radial isolation component 46 and a first, axial isolation component 50. The first radial isolation component 46 has been joined to the first axle member 34, has been configured to extend at least substantially radially from the first axle member 34, and has been configured to bend under the horn-life range of sonic frequencies. Additionally, the first radial isolation component 46 can dynamically bend to provide transverse displacements that are directed along a thickness dimension of the radial isolation component. The first, axial isolation component 50 has been joined to an operative portion of the first, radial isolation component 46, has been configured to extend axially from the first, radial isolation component. In a particular aspect, the first axial isolation component 50 can extend from the first radial isolation component 46 with a substantially cantilevered configuration. The first axial isolation component 50 can be configured to operatively flex and bend under the horn-life range of sonic frequencies. Additionally, the first axial isolation component 50 can dynamically bend to provide transverse displacements that are directed along a thickness dimension of the axial isolation component.

[0109] In a further aspect, the second, radial isolation component 48 can be joined to the second axle member 36, has been configured to extend at least substantially radially from the second axle member 36, and has been configured to bend under the horn-life range of sonic frequencies. Additionally, the second radial isolation component 48 can dynamically bend to provide transverse displacements that are directed along a thickness dimension of the second radial isolation component. The second, axial isolation component 52 can be joined to an operative portion of the second, radial isolation component 48, and can be configured to extend axially from the second, radial isolation component. In a particular aspect, the second axial isolation component 52 can extend from the radial isolation component 48 with a substantially cantilevered configuration. The second axial isolation component 52 can be configured to operatively flex and bend under the horn-life range of sonic frequencies, and can dynamically bend to provide transverse displacements that are directed along a thickness dimension of the second axial isolation component.

[0110] In still another feature, the horn member can be configured to exhibit very small deflections when subjected to a large applied load. Additionally, the horn member can cooperate with a proximally located, rotary anvil member to more reliably provide a substantially fixed gap therebetween during ordinary operation.

[0111] With reference to FIGS. 11 through 13, the horn member 28 can be securely and fixedly held in a bridge-position with a plurality of bearing members, such as provided by rotational bearings 66 and 68. Additionally, the bearings can be held with associated support mounts, such as provided by mounts 70 and 72. The bearing members can be arranged with a bearing member located at each axial side of the horn member 28. Additionally, each bearing member can be spaced from its corresponding, axial side of the horn member. The bearing members 66 and 68 can also be operatively connected to corresponding couplers 58 and 60, respectively, in a manner that can hold the couplers in a substantially fixed position that exhibits high rigidity and stiffness. The first coupler 58 can connect between the first isolation member 42 and the first rotational bearing 66, and similarly, the second coupler 60 can connect between the second isolation member 44 and the second rotational bearing 68. Additionally, the first rotational bearing 66 can support the first rotatable coupler 58 in configuration that exhibits high rigidity, and the second rotational bearing 68 can support the second rotatable coupler 60 in configuration that exhibits high rigidity. Appropriate booster members and wave-guides can be configured to extend through the couplers and operably connect to the axle members 34 and 36, and to the horn member 28.

[0112] The rotational bearings 66 and 68 can be high-precision bearings that exhibit low levels of run-out. In desired arrangements, the rotational bearings can be tapered, printing press bearings. For example, the bearings can be Part No. 458681, printing press bearings that are available from SKF U.S.A., a business having offices located in King of Prussia, Pa.

[0113] The first isolation member 42 can be joined to the first rotatable coupler 58 that is supported by the first rotational bearing 66. Similarly, the second isolation member 44 can be operatively joined to the second rotatable coupler 60 that is supported by the second rotational bearing 68.

[0114] The first isolation member 42 can be joined to the first coupler 58 by including an interference, friction-fit. For example, he first coupler 58 can provide a first coupler opening 62, and the first, axial isolation component 50 of the first isolation member 42 can be operatively positioned and secured in the first coupler opening 62. Similarly, the second isolation member 44 can be joined to the second coupler 60 by including an interference, friction-fit. The second coupler 60 can provide a second coupler opening 64, and the second, axial isolation component 52 of the second isolation member 44 can be operatively positioned and secured in the second coupler opening 64.

[0115] In a particular aspect, the first coupler 58 can provide a first, substantially cylinder-shaped, coupler opening 62 into which the first axial isolation component 50 of the first isolation member 42 can be operatively positioned and secured. Similarly, the second coupler 60 can provide a second, substantially cylinder-shape, coupler opening into which the second axial isolation component 52 of the second isolation member 44 can be operatively positioned and secured.

[0116] As representatively shown, the first isolation member 42, and particularly the first, axial isolation component 50 can include an extending, first flange portion 54 which can be operatively positioned and secured in the first coupler opening 62. The first coupler flange 54 can include a generally radially extending section and a generally axially extending section. Additionally, the first coupler flange portion 54 can be operatively joined to the first coupler opening 62 by including an interference, friction-fit. Similarly, the second isolation member 44, and particularly the second axial isolation component 52 can include an extending, second flange portion 56, and the second flange portion can be operatively positioned and secured in the second coupler opening 64. The second coupler flange 56 can also include a generally radially extending section and a generally axially extending section, and the second coupler flange portion 56 can be operatively joined to the second coupler opening 64 by including an interference, friction-fit.

[0117] A first mount 70 can support the first rotational bearing 66, and in a particular aspect, the first mount can support the first rotational bearing with a configuration that exhibits high rigidity and stiffness. The first mount 70 can be axially spaced from the first axial side 30 of the horn member 28, and can be located proximate the first node plane 38 of the first axle member 34. A second mount 72 can support the second rotational bearing 68, and in a particular aspect, the second mount can support the second rotational bearing with a configuration that exhibits high rigidity and stiffness. The second mount 72 can be axially spaced from the second axial side 32 of the horn member 28, and can be located proximate the second node plane 40 of the second axle member 36. The bearing mounts can be positioned generally adjacent the node planes that can arise their corresponding axle members. As representatively shown, the first bearing support mount 70 can be positioned generally adjacent the first node plane 38 provided by the first axle member 34. Similarly, the second bearing support mount 72 can be positioned generally adjacent the second node plane 40 provided by the second axle member 36.

[0118] The first axle member 34 can provide a wave-guide which can be configured to operably direct ultrasonic energy from a suitable ultrasonic power source into the horn member 28. In a similar fashion, the second axle member 36 can be configured to provide a waveguide which can operably direct ultrasonic energy from a suitable power source into the horn member 28.

[0119] With reference to FIGS. 11 through 13, an ultrasonic booster member 74 can be operatively connected to the first axle member 34, and a first ultrasonic exciter 82 can be operably connected to the first booster member 74 by employing any conventional technique or device. For example, a conventional slip ring 78 can be employed to direct electrical power to the first exciter 82, and the first exciter can produce and direct ultrasonic energy into the first booster member 74.

[0120] As representatively shown in FIG. 13A, an optional configuration of the method and apparatus can include a second ultrasonic exciter 84. Additionally, a second booster member 76 can be operably connected to the second axle member 36, and the second ultrasonic exciter 84 can be operatively connected to the second booster member 76. A second, conventional slip ring 80 may then be employed to direct ultrasonic energy from the second ultrasonic exciter 84 into the second booster member 76. The first and second ultrasonic exciters 82 and 84 can be configured to simultaneously and cooperatively direct increased amounts of ultrasonic energy to the rotary horn member 28. The effective cooperation of the ultrasonic exciters can be provided and regulated by employing conventional control techniques and systems that are well known in the art and available from commercial vendors.

[0121] As representatively shown, the support frame 22 can include upright-members that are configured to fixedly hold the anvil member 86 at a location that is generally superjacent the cooperating horn member 28. Optionally, the method and apparatus can be configured with any other operable arrangement between the anvil member and horn member. For example, the anvil member 86 can be fixedly held and positioned generally subjacent the cooperating horn member 28, or at a height-level that is approximately equal to the height-level of the horn member.

[0122] In the various attachments and securements employed in the constructions of the method and apparatus of the invention, it should be readily apparent that any conventional attachment or securement technique may be employed. Such techniques may, for example, include adhesives, welds, screws, bolts, rivets, pins, latches, clamps or the like, as well as combinations thereof.

[0123] Similarly, it should be readily apparent that any conventional material may be employed to construct the various members and components of the method and apparatus. Such materials can include synthetic polymers, fiberglass-resin composites, carbon fiber-resin composites, metals, metallic composites, ceramic composites, and the like, as well as combinations thereof. For example, suitable metals may include steel, aluminum, titanium or the like, as well as combinations there of. The materials are typically selected to provide desired levels of strength, hardness, low vibrational damping, toughness, fatigue resistance, durability, ease of manufacture, and ease of maintenance.

[0124] The dimensions of the various components can depend upon the particular application of the method and apparatus, and can be determined by employing standard engineering techniques. For example, the dimensions of the components can be determined by ascertaining the desired peak operating load and by setting the stress limits to a selected safety factor (e.g. a safety factor of ten) to help assure adequate operating life and fatigue resistance.

[0125] The rotary horn member 28, the corresponding wave guide/axle members, the corresponding isolation members and other cooperating components can be constructed as a unitary assembly which is integrally formed from a single piece of material. The one-piece design can eliminate interfaces that can be sources for excessive wear and excessive heat generation. Such interfaces can also contribute to the build up of tolerance errors during machining. Such tolerance errors can make it difficult to maintain a desired level of concentricity at the working surface of the rotary horn. As a result, the various configurations of the method and apparatus can reduce cost, provide increased stiffness, can operate within smaller tolerance ranges and can provide more consistent performance during high speed production.

[0126] It should be readily appreciated that the various rotational components can be dynamically spin-balanced to reduce wear, reduce vibrations, better maintain desired positionings and further improve the performance of the desired bonding operation. Each of the components may be dynamically balanced individually or in an operative combination with other components, as desired.

[0127] Although various illustrative and representative configurations have been described in detail herein, it is to be appreciated that other variants, modifications and arrangements are possible. All of such variations, modifications and arrangements are to be considered as being within the scope of the present invention. 

1. An ultrasonic processing apparatus, comprising: a rotatable, ultrasonic horn member having a first axial side and a second axial side; a first, rotatable axle member which is operatively joined to said first axial side of said horn member; a first isolation member which is operatively joined to said first axle member, said first isolation member capable of bending under a horn-life range of sonic frequencies to provide an operative component of motion along a radial direction of said first isolation member and an operative component of motion along an axial direction of said first isolation member; a second, rotatable axle member which is operatively joined to said second axial side of said horn member; a second isolation member which is operatively joined to said second axle member, said second isolation member capable of bending under a horn-life range of sonic frequencies to provide an operative component of motion along a radial direction of said second isolation member and an operative component of motion along an axial direction of said second isolation member.
 2. The apparatus as recited in claim 1, wherein said first isolation member has a first, radial isolation component and a first, axial isolation component; said first, radial isolation component is joined to said first axle member, is configured to extend at least radially from said first axle member, and is configured to bend under a horn-life range of sonic frequencies; said first axial isolation component is joined to an operative portion of said first radial isolation component, is configured to extend axially from said first radial isolation component, and is configured to bend under said horn-life range of sonic frequencies; said second isolation member has a second, radial isolation component and a second, axial isolation component; said second, radial isolation component is joined to said second axle member, is configured to extend at least radially from said second axle member, and is configured to bend under said horn-life range of sonic frequencies; said second, axial isolation component is joined to an operative portion of said second, radial isolation component, is configured to extend axially from said second radial isolation component, and is configured to bend under said horn-life range of sonic frequencies.
 3. The apparatus as recited in claim 1, wherein said first radial isolation component extends substantially continuously along a circumferential direction of said first isolation member, and said second radial isolation component extends substantially continuously along a circumferential direction of said second isolation member.
 4. The apparatus as recited in claim 1, wherein said first radial isolation component extends discontinuously along a circumferential direction of said first isolation member, and said second radial isolation component extends discontinuously along a circumferential direction of said second isolation member.
 5. The apparatus as recited in claim 1, wherein said first and second radial isolation components are substantially disk-shaped.
 6. The apparatus as recited in claim 1, wherein said first axial isolation component is configured to provide an axial extension from said first radial isolation component, and said second axial isolation component is configured to provide an axial extension from said second radial isolation component.
 7. The apparatus as recited in claim 1, wherein said first axial isolation component is configured to provide an axial extension from a radially outboard section of said first radial isolation component, and said second axial isolation component is configured to provide an axial extension from a radially outboard section of said second radial isolation component.
 8. The apparatus as recited in claim 6, wherein said first axial isolation component is configured to provide a substantially continuous axial extension from said first radial isolation component, and said second axial isolation component is configured to provide a substantially continuous axial extension from said second radial isolation component.
 9. The apparatus as recited in claim 6, wherein said first axial isolation component is configured to extend substantially continuously along a circumferential direction of said first isolation member, said second axial isolation component is configured to extend substantially continuously along a circumferential direction of said second radial isolation member.
 10. The apparatus as recited in claim 6, wherein said first axial isolation component is configured to extend discontinuously along a circumferential direction of said first isolation member, and said second axial isolation component is configured to extend discontinuously along a circumferential direction of said second isolation member.
 11. The apparatus as recited in claim 6, wherein said first and second axial isolation components are substantially cylinder-shaped.
 12. The apparatus as recited in claim 1, further including at least a first rotatable coupler which is supported by a rotational bearing; wherein said first isolation member is operatively joined to said first coupler.
 13. The apparatus as recited in claim 12, wherein said first coupler provides a first coupler opening; and said first axial isolation component is operatively positioned and secured in said first coupler opening.
 14. The apparatus as recited in claim 12, wherein said first isolation member is joined to said coupler by including an interference, friction-fit.
 15. The apparatus as recited in claim 12, wherein said first coupler has a first coupler opening; said first axial isolation component includes an extending, first flange portion; and said first flange portion is operatively positioned and secured in said first coupler opening.
 16. The apparatus as recited in claim 15, wherein said first flange portion is operatively joined to said first coupler opening by including an interference, friction-fit.
 17. The apparatus as recited in claim 1, further including: a rotatable anvil member which is cooperatively positioned proximate said horn member; and an ultrasonic exciter which is operatively connected to said horn member.
 18. The apparatus as recited in claim 1, wherein said first radial isolation component has a length and thickness which allow said first radial isolation component to operatively bend without excessive fatigue; said first axial isolation component has a length and thickness which allow said first axial isolation component to operatively bend without excessive fatigue.
 19. The apparatus as recited in claim 1, wherein said rotatable horn member has a maximum deflection of not more than about 0.004 mm under a force of 445 N.
 20. The apparatus as recited in claim 1, wherein said rotatable horn member has a maximum run-out of not more than about 0.018 mm at a rotational speed of 5 revolutions/min.
 21. An ultrasonic processing apparatus, comprising: a rotatable, ultrasonic horn member having a first axial side and a second axial side; a first, rotatable axle member which is operatively joined to said first axial side of said horn member, said first axle member capable of providing a first node plane; a first isolation member which is operatively joined to said first axle member, and has a location that is operatively proximate said first node plane of the first axle member, said first isolation member having a first, radial isolation component and a first, axial isolation component; wherein said first, radial isolation component is joined to said first axle member, is configured to extend at least radially from said first axle member, and is configured to bend under a horn-life range of sonic frequencies; said first axial isolation component is joined to an operative portion of said first radial isolation component, is configured to extend axially from said first radial isolation component, and is configured to bend under said horn-life range of sonic frequencies; a second, rotatable axle member which is operatively joined to said second axial side of said horn member, said second axle member capable of providing a second node plane; a second isolation member which is operatively joined to said second axle member and has a location that is operatively proximate said second node plane of the second axle member, said second isolation member having a second, radial isolation component and a second, axial isolation component; wherein said second, radial isolation component is joined to said second axle member, is configured to extend at least radially from said second axle member, and is configured to bend under said horn-life range of sonic frequencies; said second, axial isolation component is joined to an operative portion of said second, radial isolation component, is configured to extend axially from said second radial isolation component, and is configured to bend under said horn-life range of sonic frequencies; a first coupler which connects between said first isolation member and a first rotational bearing, said first coupler providing a first coupler opening into which said first isolation member is operatively positioned and secured; and a second coupler which connects between said second isolation member and a second rotational bearing, said second coupler providing a second coupler opening into which said second isolation member is operatively positioned and secured.
 22. An ultrasonic processing apparatus, comprising: a rotatable, ultrasonic horn member; a rotatable first axle member which is operatively joined to a first axial side of said horn member, said first axle member capable of providing a first node plane; a first isolation member which is operatively joined to said first axle member and is located operatively proximate said first node plane of the first axle member, said first isolation member having a first radial isolation component and a first axial isolation component; wherein said first radial isolation component is joined to said first axle member, is configured to extend at least radially from said first axle member, has a substantially annular-shape, and is configured to bend under a horn-life range of sonic frequencies; said first axial isolation component is joined to an operative portion of said first radial isolation component, is configured to extend axially from said first radial isolation component, has a substantially cylinder-shape, and is configured to bend under said horn-life range of sonic frequencies; a rotatable second axle member which is operatively joined to a second axial side of said horn member, said second axle member capable of providing a second node plane; a second isolation member which is operatively joined to said second axle member and is located operatively proximate said second node plane of the second axle member, said second isolation member having a second radial isolation component and a second axial isolation component; wherein said second radial isolation component is operatively joined to said second axle member, is configured to extend at least radially from said second axle member, has a substantially annular-shape, and is configured to bend under said horn-life range of sonic frequencies; said second axial isolation component is joined to an operative portion of said second radial isolation component, is configured to extend axially from said second radial isolation component, has a substantially cylinder-shape, and is configured to bend under said horn-life range of sonic frequencies; a first coupler which connects between said first isolation member and a first rotational bearing, said first coupler providing a first, substantially cylinder-shape, coupler opening into which said first axial isolation component is operatively positioned and secured; a second coupler which connects between said second isolation member and a second rotational bearing, said second coupler providing a second, substantially cylinder-shape, coupler opening into which said second axial isolation component is operatively positioned and secured; a first mount for supporting said first rotational bearing, said first mount axially spaced from said first axial side of said horn member; a second mount for supporting said second rotational bearing, said second mount axially spaced from said second axial side of said horn member; a rotatable anvil member which is cooperatively positioned at a selected spaced distance from said horn member; an anvil drive which can rotate said anvil member to provide an anvil, peripheral speed of at least about 5 m/min; a horn drive which can rotate said horn member to provide a horn, peripheral speed which substantially equals said anvil peripheral speed; and at least a first ultrasonic exciter which is operatively connected to said horn member and can provide an operative amount of ultrasonic energy at a frequency within the range of about 15-60 KHz; wherein said horn member is configured to exhibit a static deflection of not more than about 0.004 mm at a load of 445 Newtons; and said horn member and anvil member are configured to provide a substantially constant horn-anvil gap which is at least about 0.01 mm.
 23. An ultrasonic processing method, comprising: a rotating of an ultrasonic horn member; said horn member having been operatively joined to a rotatable first axle member, and to a rotatable second axle member; said first axle member having been operatively joined to a first isolation member, said first isolation member capable of dynamically bending and flexing under a horn-life range of sonic frequencies to provide an operative component of motion along a radial direction of the first isolation member and an operative component of motion along an axial direction of the first isolation member; and said second axle member having been operatively joined to a second isolation member, said second isolation member capable of dynamically bending and flexing under said horn-life range of sonic frequencies to provide an operative component of motion along a radial direction of the second isolation member and an operative component of motion along an axial direction of the second isolation member.
 24. The bonding method as recited in claim 23, wherein said first isolation member has been configured with a first, radial isolation component and a first, axial isolation component; said first, radial isolation component has been operatively joined to said first axle member in a configuration that extends at least radially from said first axle member, and configured to operatively bend when subjected to said horn-life range of sonic frequencies; said first, axial isolation component has been joined to an operative portion of said first radial isolation component with a configuration that extends at least axially from an operative portion of said radial isolation component, and has been configured to operatively bend when subjected to said horn-life range of sonic frequencies said second isolation member has been configured with a second radial isolation component and a second axial isolation component; said second radial isolation component has been joined to said second axle member, has been configured to extend at least radially from said second axle member, and has been configured to bend under said horn-life range of sonic frequencies; said second axial isolation component has been joined to an operative portion of said second radial isolation component, has been configured to extend axially from said second radial isolation component, and has been configured to bend under said horn-life range of sonic frequencies.
 25. The method as recited in claim 23, further including an operative coupling of said first isolation member to a first rotational bearing, and an operative coupling of said second isolation member to a second rotational bearing.
 26. The method as recited in claim 23, further including: a cooperative positioning of a rotatable anvil member proximate to said horn member; and an operatively joining of an ultrasonic exciter to said horn member.
 27. The method as recited in claim 23, further including: a cooperative positioning of a rotatable anvil member proximate to said horn member; an operatively joining of a first ultrasonic exciter to said first axle member; and an operatively joining of a second ultrasonic exciter to said second axle member.
 28. A bonding method, comprising: a rotating of an ultrasonic horn member having a first axial side and a second axial side; said first axial side of said horn member having been operatively joined to a first, rotatable axle member which can provide a first node plane; said first axle member having been operatively joined to a first isolation member; said first isolation member having been located operatively proximate said first node plane of the first axle member, with said first isolation member having a first radial isolation component and a first axial isolation component; wherein said first radial isolation component has been joined to said first axle member, has been configured to extend at least radially from said first axle member, and has been configured to bend under a horn-life range of sonic frequencies without excessive fatigue; said first axial isolation component has been joined to an operative portion of said first radial isolation component, has been configured to extend axially from said first radial isolation component, and has been configured to bend under said horn-life range of sonic frequencies without excessive fatigue; said second axial side of said horn member having been operatively joined to a second, rotatable axle member which can provide a second node plane; said second axle member having been operatively joined to a second isolation member; said second isolation member having been located operatively proximate said second node plane of the second axle member, with said second isolation member having a second radial isolation component and a second axial isolation component; wherein said second radial isolation component has been joined to said second axle member, has been configured to extend at least radially from said second axle member, and has been configured to bend under said horn-life range of sonic frequencies; said second axial isolation component has been joined to an operative portion of said second radial isolation component, has been configured to extend axially from said second radial isolation component, and has been configured to bend under said horn-life range of sonic frequencies; said first isolation member having been connected to a first rotational bearing with a first coupler which provides a first coupler opening into which said first axial isolation component has been operatively positioned and secured; and said second isolation member having been connected to a second rotational bearing with a second coupler which provides a second coupler opening into which said second axial isolation component has been operatively positioned and secured.
 29. A processing method, comprising: a rotating of an ultrasonic horn member which has a first axial side and a second axial side; said first axial side of said horn member having been operatively joined to a rotatable first axle member which can provide a first node plane; said first axle member having been operatively joined to a first isolation member which is located operatively proximate said first node plane of the first axle member, said first isolation member having a first radial isolation component and a first axial isolation component; wherein said first radial isolation component has been joined to said first axle member, has been configured to extend at least radially from said first axle member, has a substantially annular-shape, and has been configured to dynamically bend under a horn-life range of sonic frequencies; said first axial isolation component has been joined to an operative portion of said first radial isolation component, has been configured to extend axially from said first radial isolation component, has a substantially cylinder-shape, and has been configured to dynamically bend under said horn-life range of sonic frequencies; said second axial side of said horn member having been operatively joined to a rotatable second axle member which can provide a second node plane; said second axle member having been operatively joined to a second isolation member which has been located operatively proximate said second node plane of the second axle member, with said second isolation member having a second radial isolation component and a second axial isolation component; wherein said second radial isolation component has been operatively joined to said second axle member, has been configured to extend at least radially from said second axle member, has a substantially annular-shape, and has been configured to dynamically bend under said horn-life range of sonic frequencies; said second axial isolation component has been joined to an operative portion of said second radial isolation component, has been configured to extend axially from said second radial isolation component, has a substantially cylinder-shape, and has been configured to dynamically bend under said horn-life range of sonic frequencies; a first coupler having been connected between said first isolation member and a first rotational bearing, said first coupler providing a first, substantially cylinder-shape, coupler opening into which said first axial isolation component has been operatively positioned and secured; a second coupler having been connected between said second isolation member and a second rotational bearing, said second coupler providing a second, substantially cylinder-shape, coupler opening into which said second axial isolation component has been operatively positioned and secured; said first rotational bearing having been supported by a first mount, said first mount axially having been spaced from said first axial side of said horn member; said second rotational bearing having been supported by a second mount, said second mount axially having been spaced from said second axial side of said horn member; a rotatable anvil member having been cooperatively positioned at a selected spaced distance from said horn member; said anvil member having been rotated by an anvil drive to provide an anvil, peripheral speed of at least about 5 m/sec; said horn member having been rotated by a horn drive to provide a horn, peripheral speed which substantially equals said anvil peripheral speed; said horn member having been operatively connected to at least a first an ultrasonic exciter which can provide an operative amount of ultrasonic energy at a frequency within the range of about 15-60 KHz; said horn member having been configured to exhibit a static deflection of not more than about 0.004 mm at a load of 445 Newtons; and said horn member and anvil member having been configured to provide a substantially constant horn-anvil gap which is at least about 0.01 mm. 